In today's terms it commonly used to emphasise shock and/or amazement or anger. However it came into large use in the British context during World Wars' 1 & 2 whereby soldiers would describe it as a "bloody hell".
The intense meaning has waned over the years to become a common 'filler' in utterance. However, given if someone survived a nuclear war, if it happened 21st C, would it change to "nukem hell!" ? Sounds a bit Australian to me.